Improvement



W. H. SMITH.

Projectile.

Paten'ted Oct; 11, 1864.

NirEn XV. H. SMITH, OF BIRMINGHAM, CONNEOTICUT.

IMPROVEMENT BN JACKETS FORSUB-CALI BER PROJECTILES.

Specilication forming part of Letters Patent No. 34,670., dated October11,1861.

To all whom iv' may concern:

Be it known that I, W'. H. SMITH, of Birmingham, of the county of NewHaven, in the State of Connecticut, have invented certain .new anduseful Improvements in Projectiles for Ordnance; and I do hereby declarethat i'he following is a full and exact description thereof, referencebeing had to the accompanying drawings, making part of this application.

My present invention relates to that' kind of projectile which isdesignated sub-ealiber.

Previous to my invention this kind of project- 4 ile has had itscentering case or jacket made to fit to the body or bolt of the shotnear its forward and rear ends, and about equal in dianeter throughoutits entire length to the bore of the gun-as, for instance, as shown inLetters Patent granted to me on the 23d day of December, 1862; but withthe centering holder case or jacket thus made the large diameter of thelatter induced to so much weight as to make it very objectionable, sinceit is necessary to produce a successful sub-caliber projectile that acertain proportion of weights shouldexist between the bolt or body andits surrounding case or centering-jacket, and it was impracticable toattain this proportion with the jacket of so great diameter, and at thesame time have the latter suflieiently strong. These objections wereovercome by making the jacket of another form, in which the greaterportion of it corresponded in diameter (internal) to the diameter of thebolt, only a small enlarged portion at its front end corresponding tothe diameter of the bore of the gun, and by combining with a jacket soshaped a washer or band arranged on its rear end, which also filled thebore of the gun, as fully shown and described in Letters Patent grantedtonne on the 5th day of January, 1864:; but this mode of constructing asub-caliber shot, though possessing some advantages over methodspreviously known and being very good, still embodies some practicalobjections, among which may be mentioned the expense and labor ofconstruction, and the liability of the small rear band to be upset orderanged bythe excess of pressure on the upper surface of the project'-ile as it lay in the bore when the explosion of the charge takes place.

My invention has for its objects to avoid these objections, and toproduce a sub-caliber projectile which willbe more desirable in everyrespect than any heretofore made; and to these ends my present inventionconsists in making the cente'ring jacket or case with both its forwardand rear ends large enough to fill the bore of the gun, (of equaldiameter,) and the portion intervening between the enlarged ends smallenough to fit closely to the body or bolt therein inclosed, whereby thecentering case or jacket is made capable of effectually holding the boltor body centrally in the bore of the gun, both at rear and front end ofthe former, and at the same time have the greater portion of its lengthso small in diameter as to involve little weight.

To enable those skilled in the art to make and use my invention, I willproceed to de-` scribe the construction and operation of my improvedproj ectile, referring by letters to the accompanying drawings, formingpart of this application, and in which- Figure 1 is a longitudinalelevation of one of my improved projectiles. Fig. 2 is a bottom view ofthe same. Fig. 3 is a longitudinal central section, and Fig. 4 is across-section at the line X X, Fig. 1.

ignated by the same letter of reference.

A is the body or bolt of the proj ectile, which I propose to make ofsteel, (or iron tipped with steel,) of a tapering form, as clearlyshown, (being largest at its extreme forward portion,) with its forwardend dished out slightly, as seen at IL, Fig. 3.

B is the centering holder ca-se or j aeket, by which the body A is heldand guided during its flight through the bore of the gun, and by whichit is also rotated on its axis, the said D, (taking into the rifles ofthe gun,-) and being so interlocked (or dogged) by means of a depressionin its rear end and a correspondingly-shaped proj eetion on the rear endof bolt A as to cause the latter to always turn with it. The sabot D iscomposed of a simple brass band cast onto the base of the jacket B insuch a manner as to be expanded or distended radially by the action ofthe gases entering into the space or crevice f. This peculiarcombination and arrangement of packingring D is made the subject ofanother appli- In the several figures the same part is deijacket B beingrotated by means of a sabot,

eation filed simultaneously with this,where it Will be found fullydescribed. The jacket B, it will be seen by reference to the drawings,is formed with its extreme forward and rear portion of a diameteradapted to fill the bore of the gun, while the intermediate and greaterportion of it is made small enough to just fit over the body A, which isturned to fit into the finished interior of said jacket. If -the metalof which B is formed is sufficiently strong, the forward enlarged endmay be cast hollow, as seen at g, to lighten it. The enlarged portionsare turned to fit the bore of the gun, as shown at 1 2 3 4, and theintermediate portion may be covered over with a filling of some lightmaterial, such as papiermach, or any other suitably light and tenaciousmaterial, as illustrated by the red lines coming out flush with theperimeters of the enlarged front and rear ends of jacket B, andpresenting, in connection with then, asinooth cylindrical exterior.

Z) b are corner braces or webs, which may be found desirable foraffording greater strength to the enlarged base of jacket B, whichcarries the sabot, receives the shock of the explosion, and has impartedto it the twist of the rifles.

The operation of this improved proj ectile in receiving the force of theexplosion and in its flight is pretty much the same as that of my othersub-caliber projectiles. The explosive gases expand the packing-ring Dinto the grooves of the gun, and the shot is projected in a successfulmanner, the case or jacket B traveling with tle bolt A until the lattermeets with a resisting medium too dense for the case B to penetrate,when the latter is stripped or broken off.

My improved shot, like most subcaliber projectiles, is particularlyintended for heavy ordnance and operating against iron armors whereaccuracy of range, great force of impact, and penetration are the mainrequisites.

It will be seen that by making the centering-case B with both its rearand forward ends of a diameter equal to that of the bore of the gun apermanent and reliable support is afforded at the rear as well as at theforward end of the body A, to hold and guide it centrally in the boreindependently of the sabot, while at the same time the jacket is of suchform as to involve very little weight, and to induee to economy in themanufacture of the shot, and in these combined adantages it will be seenthat my present form of jacket, B, is more desirable than any heretoforemade or suggested.

Experiment and practice have shown that in consequence of the greateropportunity afforded to the explosive gases to escape around the upperportion of the shot as it lay in the bore, (for the shot cannot fit thebore closely, and when at rest in the bore will of course leave a largercrevice between its upper portion and the bore than between the bore andits lower surface,) they will exert so much more pressure at this pointthan at any other as to cause the projectile to be forced downward ontothe bore of the gun considerably before the packing has expanded and theforce becomes equalized. WVhere the base of the shot is sustained onlyby a sabot or by a washer, this objectionable depression of the shot occurs to a much greater extent than it can with my improved form ofjacket B, with which, it will be seen, the solid stock of the jackethelps to sustain the body or bolt A centrally in the bore against thisaction of the gases.

I deem the form and proportions of the jacket B shown to be' about thebest, but do not of course limit myself to the precise shape orproportions shown, so long as the characteristic features of formationare embodied.

Having fully explained the construction and operation of my improvedsub-caliber projectile, what I claim therein as new, and desire tosecure by Letters Patent, is-

Making the netallic holder-case or centering jacket to fill the bore ofthe gun at both its rear and forward ends, and its intermedi ate portionto fit to the bolt or body of the shot, substantially as and for thepurposes set forth.

In testimony whereof I have hereunto set my hand and seal this 7th dayof June, 1864:.

NV. H. SMITH. [n s] In presence of J. N. MOINTIRE, ANDREW I. Tom).

